Burgiar alarm and trap



Patented Jan. 23, 1940 UNITE STATES "PATENT OFFICE 2 Claims.

This invention relates generally to burglar alarms and traps.

The main object of the invention is to provide an arrangement of conductors or strips on a 5 fioor or mat, together with means for energizing these conductors with high tension electrical energy in such manner that a burglar or robber standing on the conductors when they are energized, will be so shocked and rendered harmless that his nefarious purpose will be foiled and his capture made easy.

Another object is to provide a method of preparing a floor or mat for the above purpose which comprises the placing of parallel strips of thin metal foil on the floor connecting alternate sets of strips to the two sides of the energizing circuit, coating the strips and adjacent floor surfaces with a metallic conductive paint to increase the energized area of the floor, filling in the intervening spaces on the floor surface with a nonconductive paint and finally, painting the entire surface of the floor with a non-conductive paint to conceal the strips.

The foregoing and other objects, together with means whereby the same may be carried into effeet, will best be understood from the following detailed specification. in which reference is had to the accompanying drawing, wherein:

Figure l is a plan view of a section of a floor or mat with the conductors or strips in place and showing the energizing circuit.

Figure 2 is a similar View but showing the strips coated with the conductive paint.

Referring now with more particularity to the drawing, in preparing a section of the floor F for my purpose I provide the fioor with spaced parallel strips or conductors 5 which are connected alternately together by the lateral runners or bus-strips 5 and I, so that both sides of the energizing circuit will be present between any two adjacent strips. It may here be pointed out that the invention may be applied to any desired area of the floor and to any desired fiat surface whether it be a floor, wall, panel, mat or the like, or even to the doors of safes and the like. The strips 5 and bus-strips 6 and '2' are formed of thin metal foil which is applied and held to the floor by shellac or other adhesive and so that the strips present very little projection 50 from the floor.

A high tension induction coil is connected by wires 9 and it to the strips 6 and l and is energized by a battery H or other source of electrical energy under control of a switch [2. When this switch is closed, it will thus be understood that the strips 5 will be charged with a very high tension voltage, and a burglar or robber standing on the fioor will be shocked and rendered harmless by the resulting high tension discharge between the strips which the robbers feet bridge or cross. The energy of course is of sufilcient magnitude to overcome the resistance offered by the robbers shoes and so pass through his body. For this purpose too it may be stated that the strips 5 are so spaced that the robbers feet will necessarily bridge at least an adjacent pair of the strips, no matter in what position he may be standing on the floor.

To conceal the strips 5, 6 and 1 and so prevent the robber being warned of their presence, I provide a covering for the strips as will now be described.

The strips are first coated with a metallic electrically conductive paint and this is allowed to spread over the strips out onto the floor F surrounding the strips without, howevenforming a continuous surface such as would effectively short the strips. This coating of conductive paint is designated at l3 in Figure 2 and the uncoated spaces between the strips are designated at I4. This coating it not only protects the strips 5, 6 and 7, but also, making electrical contact therewith, extends the eifective energized area of the floor, as will be understood. The spaces H are then filled in with a non-conducting paint such as shellac, to insulate between the strips and to build up or fill in the spaces up to a level with re painted strips l3. This prevents any telltale ridges in the finished surface such as might give warning that the fioor is protected. A final coating (not shown) of paint or other covring is then applied to conceal the floor and give it the desired color and finish.

With the floor preparedin this manner the strips 5, 5 and 7 are entirely concealed and it will thus be readily understood that any desired area of the floor or any other surface may be protected at very little expense. Then when a robber contacts or steps upon the protected area, closing of the circuit will cause an are or discharge between strips and through the robbers body as and for the purposes described.

As an illustrative compound for the metallic paint used on the strips 5, 6 and I at I3 I have 0 successfully employed a mixture of one pound of powdered copper, one pound of powdered zinc, one-quarter pound of powdered carbon, one percent of powdered sugar and one and one-half per cent of liquid vehicle. This is mixed to pro- F'. MOORE Jan. 23, 1940;

DEVELOPING TANK Filed July 27', 1939 \Illll lllllllhV jiwerzfr 274776225 M00 re 

